# CARD_VerifyFlashAsync

## C Specification

      #include <nitro/card.h>

      static inline void	CARD_VerifyFlashAsync(u32 dst, const void *src, u32 len,
      					      MIDmaCallback callback, void *arg);

## Description

This function asynchronously compares the data of the FLASH device with the designated memory. This function immediately returns the control.

When using this function, the access bus must be locked in advance using the `CARD_LockBackup` function.

The `CARD_WaitBackupAsync` function is used when waiting for the processing to complete. Call the `CARD_GetResultCode` function after completion in order to determine the results of the processing.

This function performs communications internally with the I/O processor through PXI. Be aware that the process will not complete if the PXI interrupt is not valid.

## Arguments

`dst` | The FLASH address of the comparison target
`src` | The memory address of the comparison source
`len` | The byte length of the data to be compared
`callback` | The callback function at the time of completion. Designate a NULL when this is not needed
`arg` | The arguments passed to the callback function at the time of completion. This is simply ignored if a NULL was designated in the callback

## Return Values

None.

## Internal Operations

This function executes asynchronous processes by use of the internal thread. For further details about this thread, please refer to the description of the `CARD_GetThreadPriority` function.

## See Also

`CARD_IsBackupFlash, CARD_WaitBackupAsync, CARD_GetResultCode, CARD_ReadFlash, CARD_WriteFlash, CARD_VerifyFlash, CARD_WriteAndVerifyFlash, CARD_GetThreadPriority`

## Revision History

11/02/2004 Corrected a link.
08/23/2004 Revised the links due to changes to the function.
08/18/2004 Initial version.